The present invention relates to laminates. More particularly, the present invention relates to a method of making a laminate and to the product prepared by such method, e.g., a laminate having increased peel strength and improved solvent resistance.
Laminates are used in a variety of products, including industrial wipers, workwear, medical fabrics, and the like. Such laminates typically consist of two or more layers of sheet materials which are bonded together by some means. In some cases, the layers making up the laminate are thermally point bonded. In other cases, the layers are bonded together by an adhesive. For example, some disposable industrial wipers consist of an inner layer of a polypropylene spunbonded web and two outer tissue layers. The outer tissue layers are bonded to the inner layer by an adhesive which is applied as an emulsion and thermally cured. However, such wiper laminates exhibit poor interlayer adhesion as indicated by low peel strengths and little or no resistance to organic solvents. While the adhesional properties could be improved by increasing the amount of adhesive and/or through the use of radiation curing, the resulting laminates would be less flexible and less soft, and would suffer a loss of other desirable properties, e.g., such surface characteristics as water wettability. Consequently, there is a need for an improved adhesive-based bonding method which overcomes such problems.